1 Perceptions of weight status Overweight or About Right? A Norm Comparison Explanation of Perceived Weight Status Eric Robinson & Inge Kersbergen Psychological Sciences, Eleanor Rathbone Building, University of Liverpool Liverpool, L69 7ZA, UK Corresponding Author: Dr Eric Robinson, above address, email - [email protected]Word Count: 3, 791 Key Words: perceived weight; weight status misperceptions; social comparison; norms; body image
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1Perceptions of weight status
Overweight or About Right? A Norm Comparison Explanation of
Given the results of Study 1, we also tested whether gender moderated the effect of feedback
condition on self-perceived weight status ratings (2x2 ANOVA); the interaction between
gender and condition was not significant (F (1, 97) = 0.14, p = .71, np2 = .001), suggesting
that our results were consistent across men and women. Although we used an experimental
design with random assignment, to further test robustness we also examined whether our
main results remained the same when controlling for demographic variables (e.g. participant
BMI, gender, age, income, education level) and this was the case.
General Discussion
In Study 1 we examined whether perceptions of how one’s own body weight compares to an
‘average’ person predicts personal evaluations of weight status. If participants believed that
their body weight was relatively ‘normal’ or slimmer than average, they were less likely to
identify their weight status as being overweight. In Study 2 we examined whether
experimentally manipulating perceptions of how one’s own body weight compares to an
‘average’ person influences personal evaluations of weight status. Results indicated that
participants led to believe their body weight was slimmer, as opposed to larger than an
average person, were less likely to identify their weight status as being ‘overweight’.
The proposal that weight status evaluations may be skewed or biased by body weight norms
has been suggested by a number of researchers 18, 20, 32, 33, but not directly examined. The
present studies provide direct experimental evidence in support of this hypothesis. The results
of the present studies are also in fitting with social comparison theories of judgement 23, 24.
13Perceptions of weight status
We propose that when individuals evaluate their own weight status they do so by comparing
their body size to their internal representation of what an ‘average’ sized body is.
This ‘norm comparison’ account may also explain why increases in obesity have been
associated with fewer individuals with overweight or obesity identifying their weight status
as being ‘overweight’ or ‘too heavy’. A person’s internal representation of what constitutes a
‘normal’ sized body is likely to be shaped by the types of bodies they frequently encounter 34-
36, so as obesity becomes more prevalent, perceptions of a ‘normal’ sized body will become
larger. The proposed norm comparison explanation of perceived weight status may also be
useful in explaining why there are socioeconomic and ethnic differences in weight
perception. Individuals from poorer areas and of Black or Hispanic background are more
likely to live in areas of high obesity prevalence and are less likely than their richer white
counterparts to identify that they are overweight or overestimate their weight status 37-39. This
may be because their internal representation of what constitutes a normal sized body is larger
due to encountering heavier body weights more frequently.
Further understanding of the types of comparisons individuals use to make weight status
judgements would now be valuable. Our findings suggest that perceptions of what constitutes
an ‘average’ body weight may be of particular importance. However, research in other
domains suggests that individuals will sometimes base self-evaluations on other types of
social comparison rather than simple ‘averageness’, such as upwards and downwards social
comparisons 28, or relative rank position in a population 29. In Study 1 we found some
evidence that how women (but not men) felt their body compared to very thin others
predicted their self-perceived weight status. One interpretation of this finding is the
internalisation of the ‘thin ideal’, whereby females may be more likely than males to assess
the appropriateness of their own body weight relative to slender females due to the value and
14Perceptions of weight status
importance attached to being feminine and thin. This may also in part explain why
overestimation of weight status tends to be more common among women than men 4, 7.
Although our focus here was on perceived normality of body weight and weight status
judgements, future work would also benefit from examining the importance of other
processes shaping weight status evaluations made about the self and others. Labels such as
‘overweight’ and ‘obese’ are likely to be viewed negatively by some, so it is conceivable that
this could promote underestimation of weight status among individuals with overweight. In
addition, both how ‘normal’ one’s own body size is perceived to be and self-perceived weight
status may be in part determined by physical characteristics like body fat distribution 40, so
further work examining this would now be valuable. The relevance that the present findings
have for other research on body image in obesity may now be interesting to examine.
Although we know that obesity tends to be linked with poor body image 41-43, not all
individuals with overweight or obesity will have low body dissatisfaction or negative body
image 41. One factor that may be important in explaining this is the extent to which an
individual believes their body size deviates from normality; until a person believes their body
size deviates from normality and is ‘overweight’, negative body image and body
dissatisfaction would presumably be rare. In addition, given that weight status is often
misperceived and skewed by body weight norms, intervention work to correct perceptions of
weight status may be beneficial. Addressing unrealistic body weight norms and reducing
overestimation of weight status among young women may be one such application. In a
similar vein it could be argued that ensuring overweight individuals are aware of their weight
status will encourage greater weight management efforts, but whether this would produce
positive outcomes is less clear. There is stigma attached to being ‘overweight’ and recent
findings suggest that individuals who perceive their weight status as being ‘overweight’ are
15Perceptions of weight status
counter-intuitively more likely to gain further weight than those who do not identify as being
overweight 6, 15, 16 . Thus, intervention work to address perceptions of weight status will need
to consider these findings carefully.
There were limitations to our studies. We sampled white US participants predominantly.
Studies designed to examine whether other demographic groups show a similar pattern of
results would now be valuable. To examine how participants believed their body size related
to other people, we had to make use of self-devised measures and it will be important in
future work to assess their validity and reliability. In both studies we measured self-reported
BMI as a proxy measure of body weight, as opposed to objectively measured BMI. Self-
reported BMI is prone to error. However, given that our main hypotheses examined the
relationship between perceived normality of weight and weight status evaluations and Study
2 used an experimental manipulation, it is unlikely that the error associated with self-reported
BMI will have affected any of the main conclusions of the present work.
Conclusions
Personal perceptions of weight status are likely to be shaped by a ‘norm comparison’ process.
As overweight becomes more ‘normal’ underestimation of weight status among individuals
with overweight and obesity will be more common.
16Perceptions of weight status
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